Word Origin & History

bivalve mollusk, c.1500, in clam-shell, originally Scottish, apparently a particular use from Middle English clam "pincers, vice, clamp" (late 14c.), from Old English clamm "bond, fetter, grip, grasp," from Proto-Germanic *klam- "to press or squeeze together" (cf. Old High German klamma "cramp, fetter, constriction," German Klamm "a constriction"). If this is right then the original reference is to the shell. Clam-chowder attested from 1822. To be happy as a clam is from 1833, but the earliest uses do not elaborate on the notion behind it, unless it be self-containment.

Example Sentences for clammed

Kellner had clammed up, and when the now suspicious editor had tried to check Colquhoun's tale personally, Colquhoun had vanished.

But he clammed up about that, hoping to keep it a secret until he could go back and claim it.

The crack above the door should not be clammed until the muffle begins to get warm.

Clammed means starvation; that is, care killed the cat; for want of food the entrails get "clammed."